P20 A Rare Case of Hereditary Mucoepithelial Dysplasia With Long Term Follow Up

Abstract

Abstract This 28-year old woman initially presented at 2 years of age with patchy alopecia, perianal erythema and widespread rough skin. Prior to her first birthday she was diagnosed with bilateral corneal ulceration and was treated initially with soft contact lenses. She had no features of ichthyosis or hyperkeratosis and teeth, nails and eyelashes were normal. The hair loss progressed with involvement of the eyebrows. On examination, there was widespread keratosis pilaris, perianal and vulval erythema and angular cheilitis. Light microscopy of the cut hair was essentially normal. A clinical diagnosis of hereditary mucoepithelial dysplasia was made at that time. She recently underwent genetic testing which has confirmed the diagnosis. She is now registered blind and wears a wig. Her IQ is normal. Hereditary mucoepithelial dysplasia (HMD; OMIM 158310) is a rare autosomal dominant genodermatosis characterised by chronic mucosal lesions associated with keratitis, non-scarring alopecia, keratosis pilaris and psoriasiform perineal intertrigo. A novel causative heterozygous pathogenic variant c.1580G>T (p.Arg527Leu) was identified in our patient in the sterol regulatory element-binding factor 1 (SREBF1) gene. This is involved in promoting the transcription of lipogenes that are associated with epidermal cholesterol and fatty acid biosynthesis. HMD is allelic with autosomal dominant IFAP showing considerable phenotypic overlap and should be considered in patient with congenital hypotrichosis.